NERVOUS SYSTEM
MANAGEMENT OF ACUTE HEAD INJURY AND CEREBRAL PROTECTION
Introduction
Brain damage due to head injury must be considered in terms of :
- Primary damage which occurs immediately and is final and irreversible.
- Secondary damage due to intracranial haematoma, oedema, hypoxia, hypotension, infection.
An ideal approach is to ensure best circumstances for recovery from insult and to anticipate and if possible prevent secondary brain damage.
INITIAL ASSESSMENT
A rapid but complete initial assessment is essential.
Establishing Airway and Ventilation
Intubation and ventilation are required in the following situations :
- Inability to protect airway
- Inadequate ventilation / oxygenation
- GCS < 8
All head injury patients must be assumed to have cervical spine injury until proven otherwise, hence cervical spine control must be present at all times.
Use thiopentone or midazolam for sedation and suxamethonium for paralysis for rapid intubation. Cricoid pressure must be applied and suction must be available as these patients are assumed to have full stomachs.
Treatment of Shock
Prompt and effective resuscitation is required. Look for causes of shock e.g. intra-abdominal injury, fractures, as shock is uncommon in isolated head injury.
Patient Transport
The patient must be stabilized before transport. Adequate sedation and paralysis should be given to prevent coughing on the endotracheal tube and a rise in intracranial pressure (ICP).
ICU MANAGEMENT
The aims if ICU management are:
- Early detection of changes in neurological status through constant observation and monitoring.
- Prevention of secondary cerebral insults e.g. hypoxia, hypercarbia,hypotension, hyponatraemia, raised ICP.
- Early diagnosis and treatment of medical and surgical problems , especially intracranial mass lesions, cerebral oedema and convulsions.
Initial targets to optimize cerebral perfusion pressure:
- maintain euvolemia : IV colloid till CVP 5 – 10 mmHg
- commence adrenaline infusion to CPP > 70 mmHg (MAP – ICP )
- Ensure normocarbia : PaCO² 35 – 40 mmHg
- Maintain measured osmolity <300 mOsmol/l
